Mailers typically include an envelope containing a document which is separate and apart from the envelope per se. The documents and envelopes frequently contain variable as well as non-variable information, i.e., generic and personalized information such as names and addresses for individual mailer recipients. Documents printed with variable and non-variable information are typically stuffed into mailers which, if the mailing envelopes contain variable information, must be matched with the variable information set forth in the documents. The matching and the stuffing of the documents into the envelopes is an expensive and time-consuming operation which, in the present invention, is automated.